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Jacquemontia is one of those plants which especially marks the turning of the seasons. Though it appears in spring, it is in late summer and fall when the growth is most notable. When Jacquemontia vines spread widely then late summer has arrived.
Jacquemontia is a member of the morning glory family. To me, the leaves and stems are more morning glory like than is the flower. Of course the flowers open in morning and close later in the day.
Jacquemontia can be found virtually everywhere. It is especially common in gardens or sites where ground has been disturbed.